计算:(x√y/x-2y√x/y)(x√y/x+2y√x/y)求你们帮帮忙啊

问题描述:

计算:(x√y/x-2y√x/y)(x√y/x+2y√x/y)求你们帮帮忙啊

(x√y/x-2y√x/y)(x√y/x+2y√x/y)
=(√xy-2√xy)(√xy+2√xy)
=-√xy * 3√xy
=-3xy